Interprofessional Near-Peer Mentoring Teams Enhance Cancer Research Training: Sustainable Approaches for Biomedical Workforce Development of Historically Underrepresented Students.

A cancer research training program explored different approaches for staffing their in-person and virtual programs for high school students. The inclusion of undergraduate near-peer mentors had a universal benefit when implemented across in-person and virtual training programs of one- and ten-week durations. Benefits are described for four stakeholder groups: the high school trainees, program staff, scientist partners, and peer mentors themselves. Peer mentors described that their involvement enhanced their own professional development and, for some, drove a new interest in cancer research. Scientist partners described that peer mentors helped translate their work in the virtual environment for high school students. High school trainees reported their sessions with peer mentors to be one of their favorite parts of the program. Interprofessional peer mentors were highly relatable to students and modeled communication and paths in biomedical research. Staff reported that peer mentors supported student engagement during community shadowing sessions, allowing staff to focus on developing the shadowing experiences with partners. The benefit of including peer mentors was substantial from all viewpoints explored. Their intensive inclusion in cancer research training programs supports sustainability and capacity building in biomedical workforce development.

Thai adaptation and reliability of three versions of the Barratt Impulsiveness Scale (BIS 11, BIS-15, and BIS-Brief).

Long, short, and brief versions of the Barratt Impulsiveness scale (BIS-11, BIS-15, and BIS-Brief) were tested in an adult Thai population. The BIS-11T and BIS-15T were translated, back-translated, and administered to a non-clinical population (n = 305) of native Thai speakers who returned 2 weeks later for re-test. BIS-Brief-T psychometrics were calculated post-hoc. Impulsivity scores were normally distributed for the BIS-11T and BIS-15T, but not BIS-Brief-T. Excellent internal consistency was observed, with Cronbach's alpha coefficients above 0.80 for all translated instruments: BIS-11T (α = 0.86), BIS-15T (α = 0.81), BIS-Brief-T (α = 0.81). A total of 260 participants completed both instruments (85%), with test-retest reliability exceeding r = 0.81. All three instruments were highly correlated (r = 0.83-0.89). Confirmatory factor analysis supports a three factor structure (attention, motor, non-planning) for BIS-15T and two factor structure for BIS-11T. BIS scales can support measurement of a range of impulsivity scores in an adult Thai population, though predictive validity of these scales remains unexplored.

Relationship between vitamin and calcium supplement use and colon cancer.

The relationship between vitamin supplement use and colon cancer was assessed in a population-based case-control study among men and women aged 30-62 years. Cases were 251 men and 193 women diagnosed with colon cancer in 1985-1989 in three counties in the Seattle metropolitan area who were identified from the Surveillance, Epidemiology, and End Results cancer registry. Controls were 233 men and 194 women identified by random digit dialing. Supplement use was assessed by questions on frequency, duration, and dose per day (for individual supplements) or type (for multivitamins) during the 10-year period ending 2 years before diagnosis. All results were adjusted for age and sex and were not confounded by other measured behaviors. The average daily intake of supplemental vitamins A, C, E, folic acid, calcium, and multivitamins during the reference period were each associated with reduced risk of colon cancer (all P for trend < 0.03). The strongest associations were for use of vitamin E (odds ratio, 0.43; 95% confidence interval, 0.26-0.71 for > or = 200 IU/day versus none) and multivitamins (odds ratio, 0.49; 95% confidence interval, 0.35-0.69 for daily use versus no use; both P for trend < 0.001). These two associations were also significant using a stricter test of trend limited to supplement users, which reduces the effect of colinearity among these exposures. Because almost all vitamin D supplementation comes from multivitamin pills, the association of vitamin D use with colon cancer could not be distinguished from that of multivitamin use. Clinical trials or cohort studies with long-term assessment would be needed before public health recommendations could be made about supplement use.

A randomised dose ranging study of recombinant tissue plasminogen activator in acute myocardial infarction.

To assess the thrombolytic efficacy and the effect on the systemic fibrinolytic system of recombinant tissue plasminogen activator doses of 20 mg, 50 mg, and 100 mg were compared in a randomised study. Tissue plasminogen activator was infused intravenously over 90 minutes in 50 consecutive patients with acute myocardial infarction of four hours' duration or less; on average the infusion was started 135 minutes (range 20 to 240) after the onset of pain. The affected artery was patent at the end of the 90 minute infusion in 14/17 (82%) of those who received 100 mg, 12/17 (71%) of those who received 50 mg, and 8/16 (50%) of those who received 20 mg. Regardless of dose, reperfusion rates were significantly better for patients treated within two hours of the onset of symptoms (81%) than for those treated in the third and fourth hours (54%). At the end of the infusion serum fibrinogen concentrations fell to 86% of the preinfusion value after 20 mg, 75% after 50 mg, and 63% after 100 mg, and similar dose dependent changes occurred in plasminogen, (alpha 2 anti-plasmin, and fibrinogen and fibrin degradation products. The mean infarct related regional third ejection fraction was 46% for patients with grade 2 or 3 reperfusion and 35% for those with grade 0 or 1. Ventricular fibrillation occurred in six (12%) patients during the infusion of tissue plasminogen activator, but no late ventricular fibrillation occurred. Bleeding was minimal, reocclusion occurred in three patients, and four patients died from cardiac causes. Recombinant tissue plasminogen activator is an effective thrombolytic agent which produces better reperfusion rates after a 50 or 100 mg dose than after a 20 mg dose. The effect on the systemic fibrinolytic system is dose dependent. Successful reperfusion results in improvement of left ventricular function.

The anaemia of chronic renal failure: a potentially treatable catabolic phenomenon?

It is proposed that the anaemia of chronic renal failure and the apparent lack of erythropoietin response is a result of increased proteolytic and lysosomal enzyme action on both the red cell and erythropoietin itself. Removal of the sialic acid from the red cell membrane is known to cause sequestration and a shortened cell survival. Similarly removal of sialic acid from the carbohydrate coat of erythropoietin both increases clearance by the liver and renders it susceptible to cleavage into inactive fragments by proteolytic attack. If the hypothesis is correct therapeutic intervention using enzyme inhibitors may offer hope for the amelioration of the anaemia.

In vitro bioassay of erythropoietic activity in serum using mouse spleen cells. The effect of heat inactivation on serum erythropoietin.

Untreated human serum is known to be toxic to in vitro assays for erythropoietin, including the mouse spleen cell assay system (MSCA). This phenomenon had previously been shown to be mediated by complement-dependent IgM heteroantibodies and can be overcome by heating the serum at 56 degrees C for 30 minutes. Using the MSCA, we have found that the toxic effect of serum could also be removed by treatment with a precipitating antibody against the C3c component of complement. The effects of the two methods of complement inactivation on the measurement of stimulatory activity in serum have been compared. For normal serum, the results after heat inactivation and antibody treatment were similar. In contrast, serum from a patient with aplastic anemia gave a result equivalent to 327 mU erythropoietin/ml after heat treatment, but after antibody treatment equivalent to 1,520 mU erythropoietin/ml. Gel permeation chromatography of unheated, heated, and antibody-treated sera showed that heating markedly reduced the activity of the erythropoietin peak. Seventy percent of the activity of partially purified urinary erythropoietin was lost during heating in the presence of normal serum. In addition, heating caused the appearance of high molecular weight compounds that are stimulatory in the MSCA. The level of this activity appeared to be directly related to the stimulatory activity of the unheated serum.

Increased plasma glycosidase and protease activity in uraemia: possible role in the aetiology of the anaemia of chronic renal failure.

We have measured plasma N-acetyl-beta-D-glucosaminidase (EC 3.2.1.30) and neuraminidase (EC 3.2.1.18) activities as markers of glycosidase activity and immunoreactive trypsin (EC 3.4.21.4) levels as a marker of proteolytic potential in the plasma of normal and uraemic subjects. The levels of all of these enzymes are significantly elevated in the plasma of uraemic subjects when compared to normal. We have postulated that the combined attack of glycosidases and proteases on erythropoietin will lead to fragmentation of this glycoprotein hormone with loss of activity. This may be a major contributory cause to the anaemia of chronic renal failure.